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So one of the things about science fiction is that people tend to go in for giant ships. Unfortunately, this has consequences. Or it should, at least.

Take the NuGalactica. It's an aircraft carrier in space that measures 4720 x 1762 x 602 feet. That makes it, very roughly, 227 times larger than the Nimitz class.

If Vipers were the size of F/A-18s, NuGalactica should be able to carry around twenty thousand of them. And in fact Vipers are just about half as long and two thirds the width of an F/A-18 (with wings folded), so if anything that number should be more like 50,000 Vipers.

Same with missiles/torpedoes. A Galaxy class has around two hundred times the volume of a modern destroyer - and a modern destroyer can tote anything from 50 to 360 missiles. Given that a photon torpedo is actually about the same cross section as a modern missile, but rather shorter, a Galaxy class should be able to carry anything from 10,000 to 70,000 of them. And a Galaxy class is quite small, compared to many of the ships out there. Multiply those numbers by 8 for the USS Vengeance, for example.

Now shows like to come up with excuses for why they don't actually do this. Galactica was an old museum relic, it only ever had the handful of Vipers in the museum to use. And the Federation is all about peace, not war, so they sacrifice armament for holodecks and replicators. Fair enough.

But what I've been thinking about lately is what would be the right way to go about this, if you were going to design a giant sci fi warship?

Say our ship is 3 miles long - a number I pick because it's about the size of the battleship in my Coalition universe, which is what got me thinking about this. Whenever I design weapons for it, I run into one of two things.

Option one, I put in a reasonable number of weapons. Say my battleship carries about 1,200 missiles/torpedoes. The trouble is, to make this work the weapons have to be HUGE. And I mean really, really... well :



You're basically left with a missile that's a spaceship of it's own, with all that implies. I ended up with missiles that have shields, and mount large numbers of decoys and drones of their own along with defensive armament in order to fight their way to the target. And bear in mind that's 1,200 of those on a battleship, most of whose internal volume is given over to toting giant antimatter cannon and fighters around. If it was a dedicated missile ship, even at this size you could probably increase that torpedo capacity tenfold.

Or Option two, I put in reasonably sized weapons. I tried scaling that torpedo down to about the size of an SS-18 ICBM, which is about the largest military missile ever used. It makes for a nice torpedo, I think... big enough to be massive and impressive, without being absurdly big. But now it's "only" a hundred feet long and ten feet across, and in that one fairly small torpedo magazine my battleship can suddenly carry nearly 90,000 of them. A dedicated missile carrier would carry almost a million.

And again, think of the logistics. I've no idea how long it takes to crane all those missile boxes into a VLS on a modern destroyer... a day, maybe? Imagine how long it takes to load 90,000 torpedoes onto a ship, let alone a million.

I face similar issues when it comes to fighters. Make a fighter roughly the size of a modern day fighter, and have the ship carry about 10,000 of them? Or give it a hundred fighters, but with each not far short of something like the Defiant in size? In other words not fighters at all but gunboats or PT boat, essentially.

Or of course there's always option three... make the ship a reasonable size!

So if you were putting together one of these monster ships that are so beloved of sci fi, what would you do? Gigantic weapons, or gigantic numbers of weapons?

Keep in mind that you still need room for all of those planes on a Nimitz class carrier so they can tow them around. For certain things like removing an engine requires room behind the plane. Of course you could assign a certain amount of square foot to each plane.
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But that is if you are going to pack it in like sardines inside the hanger.

I am curious on where you got the 20,000 number from. Where is the hanger anyway?

It is also possible that the engines or weaponry or whatever takes up a lot of space.

Of course that is Galactica and not Star Trek. Star Trek is a different animal, even between Prime verse and Abramsverse

McAvoy wrote:Keep in mind that you still need room for all of those planes on a Nimitz class carrier so they can tow them around. For certain things like removing an engine requires room behind the plane. Of course you could assign a certain amount of square foot to each plane.
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But that is if you are going to pack it in like sardines inside the hanger.

I am curious on where you got the 20,000 number from. Where is the hanger anyway?

It's just a very rough number from the scaling factor between the two ships. X times longer and Y times wider and Z times taller means XYZ times the volume and so that many more fighters/weapons. It's very rough, to be sure, but I'm just illustrating the principle that these giant ships have truly colossal internal volume to fill with stuff.

And since the Nimitz does indeed leave space to move the fighters around, take engines out and work on them, and all that, then those facilities would be scaled up in proportion too.

It is also possible that the engines or weaponry or whatever takes up a lot of space.

Possible. But then we don't really see that either.

But like I said, the point isn't so much to argue that Trek or Galactica does it "wrong". One can always find excuses for why a warship only carries a pitiful handful of tiny weapons, if one tries hard enough. I'm more interested in what would be the more practical approach if one was going to have one of these giant ships. Weapons of similar size to ours, by the hundreds of thousands? Or weapons in similar numbers to ours, but vastly larger?

Just by eyeballing it, the Nimitz class carrier's volume including deck space on the flight deck, takes up more volume in proportion to Galactica.

Galactica had at most a little over a hundred Vipers by eyeballing and from Blood and Chrome we saw much more and even more levels than the series. But we could assume because the Galactica was being converted into a museum, she never had her full complement of Vipers to warrant using all of the hanger levels.

The other issue is landing and taking off. We see multiples landing at the same time but there has to max. as safely as can be allowed.

McAvoy wrote:Just by eyeballing it, the Nimitz class carrier's volume including deck space on the flight deck, takes up more volume in proportion to Galactica.

Galactica had at most a little over a hundred Vipers by eyeballing and from Blood and Chrome we saw much more and even more levels than the series. But we could assume because the Galactica was being converted into a museum, she never had her full complement of Vipers to warrant using all of the hanger levels.

The other issue is landing and taking off. We see multiples landing at the same time but there has to max. as safely as can be allowed.

True. Landing rates would be based on the surface area of Galactica, rather than by volume.

The Galactica itself is a combination of carrier and Battleship, which will affect how both operate. From what I could see Galactica primarily operated its fighters in a defensive mode (since it had to guard the civilian fleet).

As to weapon size, it would depend on what your likely threats are going to be. If you expect to be the big ship in the sector, you might pack in more smaller munitions, to shoot down lots of smaller vessels. If you are engaging vessels of similar size, you would have a variety of missile sizes. Large ones to engage the enemy ship, plus smaller ones to try to shoot down their missiles. The anti-shipping missiles might have a few defenses (shields, smaller munitions), and similarly your short-range missiles might have a few smaller munitions to deal with the enemy missile munitions. Recursive ammo

Coalition wrote:As to weapon size, it would depend on what your likely threats are going to be. If you expect to be the big ship in the sector, you might pack in more smaller munitions, to shoot down lots of smaller vessels. If you are engaging vessels of similar size, you would have a variety of missile sizes. Large ones to engage the enemy ship, plus smaller ones to try to shoot down their missiles. The anti-shipping missiles might have a few defenses (shields, smaller munitions), and similarly your short-range missiles might have a few smaller munitions to deal with the enemy missile munitions. Recursive ammo

Well that brings up the related issue of how fighters can be a threat to capital ships.

In the present day/recent past, all warheads are in roughly the same sort of size class. A BBs guns, a torpedo, an aircraft bomb, or a missile all carry a warhead that's around a quarter ton to a ton or so. So a single aircraft can be a risk to a capital ship because even a single hit can cause catastrophic damage.

But if one goes down the route of having ship weapons being gigantic in size, but having normal sized fighters, then a single fighter could never be a threat. It would be as if battleships could fire 2000 lb shells at one another but aircraft can only carry a quarter pound bomb.

So again, you're left with the idea that fighters are really only a threat to capital ships if there are thousands and thousands of them, so their thousands of normal sized weapons are a match for the ship's few large ones.

Well first off if a ship is going to carry an absurd number of weapons it's highly likely that they'll have designed a system for rapidly loading that many weapons. When they load the ammo drum of an A-10 they don't pick up each round indvidually and put it in, at 1,200 rounds that could take a while. Instead the aircraft's ammo feed is designed to rapidly load the rounds and there's a dedicated ground cart just for loading letting them put 1,200 rounds into the aircraft in a matter of minutes. While it's hard to imagine a system that could load SS-19 sized torpedoes fast enough to load a million of them in a reasonable amount of time it's just as hard to concieve of a a 3 mile long ship.

Options, first you have multiple load points, entirely automated. You use magnetics to levitate the weapons so they are never banging around in a chute or have to be mechcanically loaded. The only restraint of speed of load would be the structure of the torpedoes themselves. Add in loading from ten or twenty points... Well lets assume you load the magazines from 20 points. You have 1,000,000 rounds to load so that's 50,000 per load point. You use maglev ammo handling and can load one torp every ten seconds. It would take you... 138 hours to load the entire ship or just about six days. Mind you this is a battleship sized dedicated missile boat going from totally empty magazines to completely full. That's a long time to load but comparatively your torps are tiny. You could increase loading points to 30, 40, 50, and they'd still be a speck on the ship's surface. You could also increase the rate of load, getting your rate down to a round per five seconds would halve the load time and to me seems doable with the right design of ammo handling. You have to stop imagining them on human scale. Compared to the ship these things are tiny, like loading 5.56mm ammo on a modern cruiser.

Another option is to load them in cells. You could theoreticaly load them metalstorm style, in a 10 x 10 box ten missles deep. That would let you ripple fire off hundreds of missiles rapidly and only require loading 1,000 of those boxes which since they'd likely be clustered around the ship, could likely be done 20 or 30 at a time.

In my mind the biggest deciding factor in big vs. little weapons is the target's armor. You have to decide how armor is going to work in your setting which will determine if little guns are even viable. Is there a damage threshold against shields? Is there some minimum damage you have to do to wear them down, some point below which they just absorb the shot and shrug it off? Do your ships rely on any physical armor? If so how tough is it?

A good real world example is the battleship. A common measure of their ability to do damage is throw rate. How much mass can they put down range in a given time? It's easy to calculate, shell mass times number of guns, times rate of fire = lbs/min. The issue with using this measure is that all shells are not created equal. You can't give a ship enough 3in guns to equal the throw rate of a 16in gun and call it even. The 16in round can hammer through the enemy's main belt while the 3in shells just sandblast the paint off. Same mass down range, but the armor can just shrug off anything under 14in with ease.

So going back to the original question, it's a matter of how armor functions. If small weapons can have an equal effect as larger ones then it's very likely you'd see ships armed with lots of smaller weapons. Lots of small weapons are easy to maintain, easy to repair, much more damage resistant, and allow you to spread your attention around. However if large weapons are needed they'll grow to the size needed to defeat the enemy's armor.

Again, going back to modern warships or tanks, big guns aren't put on them for shits and giggles, big guns are used because they need to be that big to get through the armor carried.

My personal preference is a mixture. A few massive guns and huge torpedos for dealing with enemy ships of the line and a smaller secondary battery for shooting smaller ships and adding their damage once enemy shields are breached.

Good thoughts all.

I like the combination idea, it's one I had thought about for my ships. The idea I had was that fighters in very large numbers were capable of taking on smaller ships like Frigates and Destroyers, but not battleships. Thus fleet combat consisted of two phases; one in which you use fighter attacks to take out the smaller ships in the enemy fleet, then another in which you close in and duke it out with the big ships.

Another thing of which to think is expected duration. If one of your cap ships has a common or expected mission length of a great deal of time away from port, it makes sense to maximize the number of rounds carried (which of course would be at the expense of the size of each round - there would, as Tyyr illustrated, be a lower limit to how small each round could be based on the expected defensive value of any opposition.) If, OTOH, these battleships are intended to go blow shit up, then head for port and re-arm before blowing other shit up, then it would make sense to maximize the size (and therefore, relative capability) of each round.

Good point. Have there ever been ships in the real world that were designed to carry enough ammunition to fight multiple battles without restocking?

GrahamKennedy wrote:Good point. Have there ever been ships in the real world that were designed to carry enough ammunition to fight multiple battles without restocking?

Not since the Age of Sail, AFAIK. To be fair, there also haven't been 3-mile-long interstellar battleships, either.

Mikey wrote:

GrahamKennedy wrote:Good point. Have there ever been ships in the real world that were designed to carry enough ammunition to fight multiple battles without restocking?

Not since the Age of Sail, AFAIK. To be fair, there also haven't been 3-mile-long interstellar battleships, either.

It would go to the territory size versus ship speed. How many resupply bases are around, how long to get to one.

True. At the most general, a mix of armaments per Tyyr would make sense. For more specific missions, there is absolutely nothing that states that the load-out can't change based on the specific mission.

WWII era battleships tended to carry between 250 and 400 rounds per turret. Depending on the ship that would give between 27 and 63 minutes of continuous firing before you ran dry. That would likely give you one to two, maaaaaybe three engagements before you were empty. Same thing with modern ships. A Ticonderoga only carrys about 122 VLS cells split between SAMs, SSMs, and ASW weapons. Realistically they could only get into one big engagement, maybe two before they'd be down to just their guns and CIWS.

GrahamKennedy wrote:Good thoughts all.

I like the combination idea, it's one I had thought about for my ships. The idea I had was that fighters in very large numbers were capable of taking on smaller ships like Frigates and Destroyers, but not battleships. Thus fleet combat consisted of two phases; one in which you use fighter attacks to take out the smaller ships in the enemy fleet, then another in which you close in and duke it out with the big ships.

Fighters would not be used much in a fleet battle either, because whatever a fighter can do, a missile can do as well. A fighter has to accelerate towards the target, slow down relative, accelerate back to its base, then match the base's velocity. 3-4 times the fuel needed compared to a missile that just goes. There is also the problem where fighters are limited in acceleration to the human inside, while missiles aren't. Whatever g-dampening system is available to fighters would also be available to missiles, and the hardware of a missile would require less of it too.

At best, I'd see fighters serving as control nodes for missile defense. They would provide a human to oversee a missile defense system, able to recognize patterns that a computer wouldn't, etc. Even then the human's job would be to recognize the threat, rather than actually flying or shooting, as the computer would take care of that (see A Boy and his Tank)

Or if you want small fighters attacking a battleship, have them go after surface installations. They can't crack the enemy armor, and the engines have more protection, but damaging maneuvering thrusters, strafing sensors, trying to damage enemy turrets (so direct fire weapons aren't as accurate) would be appropriate missions. Of course this is countered by the enemy warship having jammer platforms that mass more than the individual fighter, and controlled by a team of dedicated experts. If the fighter is attacking in coordination with a missile barrage it should survive, but if the fighter goes too far and is in view of the unengaged side of the enemy ship, those weapon operators will only have a single target to shoot. Since the pilots are briefed by the commander before the battle, they know what her likely tactics will be, and how to improvise when comms get jammed due to enemy action.

Even then, you could use missiles. Smart munitions would be able to aim themselves to targets they can actually affect (so no using shrapnel warheads vs heavy armor), retarget if they 'see' holes in the enemy hull, and the commanders of the Battleship would be able to broadcast updated targeting priorities to missiles in-flight. This saves time (the Commander can change her priorities without waiting for the remote platforms to recognize the differences) as the commander can just press a button, or give an order for the bridge crew to automatically transmit the new firing protocols (i.e. "Dispersal pattern Sierra"). I.e. you notice that the enemy ship is attempting to roll to bring the new weapons to bear, so you change the percentages from:
50% - weapon structures
30% - radio and laser emission sources
20% - engines and maneuvering
To:
20% - weapon structures
30% - radio and laser emission sources
50% - engines and maneuvering

A simple 1k file update, and the missiles change their attack patterns in mid-flight. You can even pass along specifics, so it would start with the missile type, and continue from there with the percentages. This way the heavy armor-piercing munitions continue their attacks on the enemy armored flanks, while the submunition warheads are redirected to go after maneuvering systems to damage all the small retrothrusters, and hopefully tag the fuel lines as well, setting up leaks or water hammer effects within the fuel network.

Hope this helps.